Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D9/00—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall
  • F28D9/0031—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits for one heat-exchange medium being formed by paired plates touching each other
  • F28D9/0043—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits for one heat-exchange medium being formed by paired plates touching each other the plates having openings therein for circulation of at least one heat-exchange medium from one conduit to another
  • F28D9/005—Heat-exchange apparatus having stationary plate-like or laminated conduit assemblies for both heat-exchange media, the media being in contact with different sides of a conduit wall the conduits for one heat-exchange medium being formed by paired plates touching each other the plates having openings therein for circulation of at least one heat-exchange medium from one conduit to another the plates having openings therein for both heat-exchange media
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D53/00—Making other particular articles
  • B21D53/02—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers
  • B21D53/04—Making other particular articles heat exchangers or parts thereof, e.g. radiators, condensers fins, headers of sheet metal
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/4935—Heat exchanger or boiler making
  • Y10T29/49366—Sheet joined to sheet

Definitions

• a method of producing heat transfer plates an assortment of heat transfer plates: and a plate heat exchanger comprising heat transfer plates included in the assortment.
• the present invention concerns a method of producing heat transfer plates, which are of the same size and have central heat transfer portions of the same shape.
• Each of the heat transfer plates has on respective sides of the heat transfer portion through holes, so called port holes, for through flow of at least one heat exchange fluid.
• each heat transfer plate has a passage portion which, when the heat transfer plate abuts against another heat transfer plate in a plate heat exchanger, is adapted to delimit a distribution passage for through flow of said heat exchange fluid.
• the passage portion extends from one of said port holes to an area in or near said heat transfer portion, which area has the same position in relation to the heat transfer portion in the different heat transfer plates.
• heat transfer plates abut against each other in a way such that they form a plate package with heat transfer passages between the heat transfer plates.
• the port holes of the heat transfer plates form port channels through the plate package.
• Plate heat exchangers are often used as evaporators in cooling systems.
• a plate heat exchanger most oftenly at least one heat exchange fluid, which is constituted by a refrigerant, flows into one of the port channels in the form of a liquid-gas mixture.
• the refrigerant is conducted through inlet or distribution passages, of the kind initially mentioned, into the heat transfer passages intended for the refrigerant.
• the refrigerant is subjected to a substantial pressure drop, whereby a distribution of the refrigerant between the different heat transfer passages as evenly as possible is achieved.
• the refrigerant evaporates by taking up heat from another heat exchange fluid flowing through adjacent heat transfer passages.
• SE 8702608-4 shows a plate heat exchanger formed with restrictions, which are adapted to reduce the pressure of a refrigerant, when it flows from a port channel into a number of heat transfer passages.
• the restrictions can be constituted by holes drilled in rings, which are arranged between the heat transfer plates around the port channel, or by holes drilled in a pipe, which is arranged in the port channel constituting inlet channel for the refrigerant.
• the heat transfer plates may abut against each other two by two around the port holes forming the inlet channel for the refrigerant, except in limited areas where inlet passages have been left.
• the restrictions can be adapted to a certain refrigerant, a certain pressure drop and a certain temperature difference.
• the object of the present invention is to produce, in a simple and cost effective way, heat transfer plates of the initially described kind, which are intended for plate heat exchangers of different kinds with respect to the pressure drop that is to be attained in their distribution passages.
• This object can be achieved, by means of the initially mentioned method of producing heat transfer plates, by providing by said punching operation each one of separate or interconnected sheet metal pieces, which are to form the said heat transfer plates, with holes in a way such that said one port hole in a first sheet metal piece becomes of a different kind than the corresponding one port hole in a second sheet metal piece, the said one port holes of the sheet metal pieces being shaped by the punching operation such that they result in finished heat transfer plates having differently sized passage portions.
• heat transfer plates for plate heat exchangers which are individually adapted for different refrigerants, can be produced at almost the same cost as heat transfer plates for plate heat exchangers, which are not individually adapted for different refrige- rants.
• the invention implies that different punching tools are used for punching of said one port holes of different kinds.
• the increase in cost for each heat transfer plate as a consequence of this, will be marginal in connection with large production series.
• Either the punching operation for punching said one port hole can be performed before the pressing operation for the shaping of the passage portions, or the two operations can be performed in the inverse order.
• the said one port holes of different kinds can be shaped circular but with different diameters; alternatively they can be given a shape differing from circular shape. In these different ways the heat transfer plates can easily be provided with differently sized passage portions.
• the heat transfer portion of a heat transfer plate is provided with a pressing pattern of depressions and elevations by a pressing operation. It is convenient to shape the passage portion of the heat transfer plate in the same pressing operation.
• the passage portion of each of the heat transfer plates is shaped so that it forms a groove.
• a distribution passage between two adjacent plates in a plate heat exchanger will be given the shape of a channel having a specific uniform through flow area. It is easy to calculate which length such a channel should have for obtainment of the desired pressure drop in a refrigerant flowing through the channel.
• the passage portion can alternatively be provided with a pressing pattern of elevations and/or depressions.
• the invention also concerns an assortment of heat transfer plates, which are of the same size and have central heat transfer portions of the same shape.
• Each of the heat transfer plates have through holes, so called port holes, on respective sides of its heat transfer portion for through flow of at least one heat exchange fluid and one passage portion which, when the heat transfer plate abuts against another heat transfer plate in a plate heat exchanger, is adapted to delimit a distri- bution passage for through flow of said heat exchange fluid.
• the passage portion extends from one of said port holes to an area in or near said heat transfer portion, which area has the same position in relation to the heat transfer portion in each of the different heat transfer plates.
• the heat transfer plates of the said assortment are characterized in that their said one port holes at the respective said passage portions are of different kinds and shaped such that the passage portions of the heat transfer plates have different sizes.
• heat transfer plates By an assortment of heat transfer plates is here to be understood at least two different kinds of heat transfer plates.
• a plate heat exchanger comprising heat transfer plates from the assortment according to the invention, either heat transfer plates of one kind or heat transfer plates of two or several kinds can be included.
• the later alternative can be suitable if the plate package of the plate heat exchanger comprises many heat transfer plates and, thus, long port channels. In such long port channels the heat exchange fluids are subjected to pressure drop.
• the distribution passages In order to obtain in this case an equal distribution of the refrigerant between the heat transfer passages the distribution passages, thus, may have to be differently sized along the port channel forming an inlet of the plate heat exchanger.
• the invention also concerns a plate heat exchanger comprising heat transfer plates of at least one kind included in the above discussed assortment.
• a plate heat exchanger of this kind is charac- terized in that the relationship between the smallest through flow area of a distribution passage and the through flow area of said one port hole is between 0,0002 and 0,05, preferably between 0,0007 and 0,017.
• fig. 1 shows a brazed plate heat exchanger
• fig. 2 shows a section along the line ll-ll through the brazed plate heat exchanger in fig. 1.
• Fig. 3, 5, 7 and 8 show corners of heat transfer plates having port portions according to different embodiments of the invention. Only the port portions of the heat transfer plates are correctly presented with respect to their function in fig. 3, 5, 7 and 8, whereas the remaining plate portions are only schematically shown.
• Fig. 4 and 6 show sections through the heat transfer plates of fig. 3 and 5, respectively.
• Fig. 1 shows a plate heat exchanger 1 designed to be used as an evaporator in a cooling system.
• the plate heat exchanger 1 comprises heat transfer plates 2, which are provided with pressing patterns of elevations and depressions and are brazed together to a plate package.
• the heat transfer plates 2 abut against each other such that a first and a second set of heat transfer passages are formed between the heat transfer plates 2 for through flow of two heat exchange fluids.
• One such end plate 3 is provided with four connection pipes 4-7.
• Every heat transfer plate 2 is provided with four port holes, each in line with one of the connection pipes 4-7, respectively.
• the port holes in the heat transfer plates 2 form four port channels through the plate package. Two of the port channels, aligned with the connection pipes 4 and 5, communicate with the first set of heat transfer passages and the other two port channels, which are aligned with the connection pipes 6 and 7, respectively, communicate with the second set of heat transfer passages.
• One of the heat exchange fluids is constituted by a refrigerant, which is intended to flow through the first set of heat transfer passages of the heat exchanger from the connection pipe 4 to the connection pipe 5. Consequently, the second heat exchange fluid is intended to flow through the second set of heat transfer passages of the plate heat exchanger 1 , suitably from the connection pipe 6 to the connection pipe 7.
• Fig. 2 shows a section through a plate heat exchanger 1 along the line ll-ll in fig. 1.
• the heat transfer plates 2 abut against each other in pairs around two 8, 9 of their port holes, forming two port channels 10 and 11 , respectively, and delimiting said first and second sets of heat transfer passages 12, 13.
• the port channel 10 and the connection pipe 5 form an outlet for the said refrigerant and are connected with the first set of heat transfer passages 12.
• the connection pipe 6 and the port channel 11 form an inlet for the second heat exchange fluid and are connected with the second set of heat transfer passages 13.
• Fig. 3 shows a corner portion of a heat transfer plate 2 according to a preferred embodiment of the invention.
• the heat transfer plate 2 is provided with a port hole 14 which is aligned with the connection pipe 4 in fig. 1.
• the port holes 14 of the heat transfer plates 2 form the port channel which together with the connection pipe 4 form the inlet for the refrigerant into the plate heat exchanger.
• Fig. 4 shows a section through four heat transfer plates 2 along the line IV-IV in fig. 3.
• the heat transfer plates 2 abut in pairs against each other around the port holes 14, the pressed grooves 16 of the heat transfer plates of each such pair forming a distribution passage in the shape of a channel 17.
• the port holes 14 form together a port channel 18.
• the refrigerant flows via the channels 17 from the port channel 18 into the heat transfer passages 12 formed between the heat transfer portions 15 of the heat transfer plates 2, the refrigerant is subjected to a pressure drop which is dependent on the length of the channels 17.
• a desired pressure drop By adaptation of the length of the channels 17 a desired pressure drop and, thus, an optimal evaporation of a specific refrigerant can be obtained.
• Fig. 5 shows the corner portion of a heat transfer plate 2 according to another embodiment of the invention.
• the heat transfer plate 2 has a port hole 21 , which together with corresponding port holes in other heat transfer plates 2 in a plate heat exchanger, wherein it is included, form the inlet channel of the refrigerant.
• a passage portion 22 of the heat transfer plate 2 by pressing has been provided with a pattern of elevations and depressions 23.
• Dotted lines 24, 25 mark punching lines along which the port hole can be punched and thus be given different diameters.
• Fig. 6 shows a section through four heat transfer plates 2 along the line VI-VI in fig. 5. However, only every second heat transfer plate 2 is provided with elevations and depressions 23 in its passage portion.
• the heat transfer plates 2 abut tightly against each other in pairs around the ports 21 except near the passage portions, where the abutment between the heat transfer plates 2 is such that a distribution passage 26 is formed between the heat transfer plates 2.
• the length of the distribution passage 26 can be shortened by enlargement of the diameter of the port hole 21.
• a further embodiment of the invention is shown in fig. 7.
• the area around the port hole 27 of a heat transfer plate 2 is here provided with a passage portion, in which a helically shaped groove 28 is pressed. Also in this embodiment the length of the groove 28 can be reduced by enlargement of the diameter of the port hole 27.
• Fig. 8 shows a corner portion of a heat transfer plate 2 according to yet another embodiment of the invention.
• the passage portion between a port hole 29 and the heat transfer portion 15 of the heat transfer plate 2 is provided with three pressed grooves 30, 31 , 32 of different lengths.
• the groove 30 will form a channel between the edge of the port hole 29 and the heat transfer portion 15.
• the groove 31 and the grooves 31 and 32, respectively will form channels between the edge of the port hole and the heat transfer portion 15. The more open channels are created the less pressure drop the refrigerant will be subjected to when it flows from the port hole to the heat transfer portion 15.
• all the heat transfer plates 2 shown in fig. 6 could be provided with elevations and depressions 23 in their passage portions 22, and in the embodiment shown in fig. 4 only every second heat transfer plate 2 would need to be provided with a pressed groove 16.
• the length of the channel 17 and the distribution passage 26, respectively could be changed by punching out a part of the heat transfer plates 2 in the way shown by the lines 33 and 34 in fig. 8, instead of by enlargement of the diameter of the port holes 14 and 21 , respectively.
• the plate heat exchanger 1 shown in fig. 1 could be designed for so called diagonal flow, i.e. the refrigerant would be intended to flow through the plate heat exchanger 1 from the connection pipe 4 to the connection pipe 6, and the other heat exchange fluid would be intended to flow through the plate heat exchanger between the connection pipes 5 and 7.
• the heat transfer plates 2 according to the invention can be produced from either separate or interconnected sheet metal pieces.
• the port hole 14; 21 ; 27; 29, which is to form part of the inlet channel of the refrigerant can be punched and, thereafter, the passage portion can be pressed.
• the passage portion is shaped in the same pressing operation as the one during which the sheet metal piece is provided with a pressing pattern in its heat transfer portion 15.
• the punching and pressing operations can be performed in either one or the other order, as mentioned earlier.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20405792

Family Applications (1)

Country Status (8)

Cited By (3)

Families Citing this family (16)

Citations (4)

Family Cites Families (3)

• 1997
  • 1997-02-14 SE SE9700518A patent/SE508474C2/sv not_active IP Right Cessation
• 1998
  • 1998-02-12 US US09/367,403 patent/US6230794B1/en not_active Expired - Fee Related
  • 1998-02-12 AU AU62340/98A patent/AU6234098A/en not_active Abandoned
  • 1998-02-12 CN CN98802577A patent/CN1087981C/zh not_active Expired - Fee Related
  • 1998-02-12 EP EP98904485A patent/EP0959994B1/en not_active Expired - Lifetime
  • 1998-02-12 JP JP53565698A patent/JP4262779B2/ja not_active Expired - Fee Related
  • 1998-02-12 DE DE69814042T patent/DE69814042T2/de not_active Expired - Lifetime
  • 1998-02-12 WO PCT/SE1998/000243 patent/WO1998035770A1/en active IP Right Grant

Patent Citations (4)

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